Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


The Respiratory System

Bio 105

Cheryl Stover

on 30 November 2012

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of The Respiratory System

Includes tubes that remove particles from incoming air & transport
air to & from lungs and air sacs where gases (oxygen & carbon dioxide) are
exchanged RESPIRATORY SYSTEM RESPIRATION Respiration is entire process of gas exchange between atmosphere & body cells
ventilation (breathing): moving air into & out of lungs
external respiration: gas exchange between blood & air in lungs
transport of gases in blood between lungs & body cells
internal respiration: gas exchange between blood & tissue cells inspiration: atmospheric pressure forces air into lungs
pressure in alveoli decreases due to contraction of breathing muscles (diaphragm & intercostals) & expansion of thoracic cavity
when breathing muscles contract, thoracic cage moves upward & outward, increasing volume (decreases pressure)
surface tension aids lung expansion
expiration: increased pressure in lungs forces air out of lungs
elastic recoil of lung tissues & surface tension within alveoli provide forces of expiration
when breathing muscles relax. thoracic cage moves downward & inward, decreasing volume (increases pressure) normal breathing is rhythmic & involuntary
respiratory center in brainstem includes portions of pons & medulla oblongata
medulla rhythmicity center controls basic rhythm of breathing
pneumotaxic area regulates breathing rate (normally ~ 12 breaths/minute)
factors affecting breathing: chemicals, stretching of lung tissues, emotional states
central chemoreceptors associated with respiratory center
blood concentrations of carbon dioxide & hydrogen ions affect chemoreceptors; stimulation of receptors increases breathing rate
peripheral chemoreceptors are in walls of certain large arteries
these chemoreceptors sense low oxygen levels; when oxygen levels are low, breathing rate increases gas exchange between blood & air occurs at alveoli, tiny air sacs clustered at distal ends of alveolar ducts
respiratory membrane: consists of alveolar & capillary walls
site of gas exchange between blood & alveoli
diffusion across respiratory membrane
partial pressure of gas is proportional to concentration of that gas in a mixture or concentration dissolved in a liquid
gases diffuse from regions of higher partial pressure to regions of lower partial pressure
oxygen diffuses from alveolar air into blood
carbon dioxide diffuses from blood into alveolar air
oxygen is primarily transported in red blood cells bound to hemoglobin protein (oxygen binds to iron of the heme group of hemoglobin)
oxyhemoglobin is unstable & releases oxygen in regions where partial pressure of oxygen is low
more oxygen is released as blood levels of carbon dioxide increase, as blood becomes more acidic, and as blood temperature increases
carbon dioxide may be carried in blood, bound to hemoglobin, or as bicarbonate ion in blood
most carbon dioxide is transported as bicarbonate ion
carbonic acid dissociates to release hydrogen ions & bicarbonate ions; buffering system in blood Breathing Mechanism respiratory cycle: one inspiration followed by one expiration
respiratory volumes measured with spirometer
tidal volume (TV): air volume that moves into & out of the lungs with each breath (~ 500 ml)
inspiratory reserve volume (IRV): air volume that can be forcibly inspired beyond tidal volume (~ 1900-3100 ml)
expiratory reserve volume (ERV): air volume that can be forcibly expired beyond tidal volume (~ 700-1200 ml)
residual volume (RV): air remaining in lungs after forced exhalation (~ 1200 ml)
inspiratory capacity (IC): TV + IRV
vital capacity (VC): TV + IRV + ERV
total lung capacity (TLC): VC + RV Respiratory air volume & capacities Control of Breathing Alveolar Gas Exchange Gas Transport The Respiratory System Respiration: Gas Exchange Oxygen Transport Carbon Dioxide Transport Respiration-Ventilation Breathing Movements
Full transcript